756 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
of tlie whole anatomical element is the sign of its death. Partial stain- 
ing of a living cell indicates that the coloured part no longer possesses 
any activity. In discussing partial staining the author demands the 
following postulates : — The colouring matter must not be toxic to the 
cellular protoplasm ; there must be an elective relation between 
the cell-elements and the stain ; the stain must be stable and capable 
of resisting the reducing power of the living cell. 
F or his experiments the author used the salamander, the frog, and the 
iris, and these were treated with twenty-four pigments. The salamanders 
received an intraperitoneal injection of a solution of the dye in sodium 
chloride. From the frogs a piece of mucosa was removed from the 
palate and then placed in the staining solution. The iris flowers were 
immersed in an aqueous solution of the pigment.' 
Artificial Colouring of Wine with Vegetable Substances. * — 
Sig. A. Scala finds that nitrite of potassium or formaldehyde added to 
a natural red wine will precipitate the colouring matter, leaving a 
liquid golden-yellow in the first case, cherry-red in the second. Ex- 
trinsic vegetable colouring matters from the fruits of elder, Phytolacca, 
&c., are not precipitated, and may thus be detected. Some anilin-reds 
behave in the same way. The first reagent mentioned is more trust- 
worthy than the second. 
Rapid Staining of Blood Corpuscles.f — Dr. H. Seelmann points out 
that Ehrlich’s method of differentiating red from white blood-corpuscles 
demands too much time and apparatus to be suitable for the busy 
physician. His method is as follows : — A drop of blood is placed on a 
slightly warmed cover-glass, dried, and fixed for five minutes in absolute 
alcohol ; the preparation is then placed in a saturated alcoholic solution 
of eosin with the addition of a quarter the volume of water ; it remains 
there half a minute and is then transferred to an aqueous alcoholic solu- 
tion of methylen-blue (1:85 of water, 15 of absolute alcohol) for about 
2-2 • 5 minutes ; thereafter it is put on the slide and examined wet, 
or dried and covered with balsam. The red corpuscles become brown- 
red ; the nuclei of the white corpuscles dark blue ; the protoplasm a 
delicate bright blue; and eosinophilous cells are similarly stained. 
The preparations cannot be compared with Ehrlich’s, but they are 
sufficiently clear for an estimate of the proportions of red and white 
corpuscles, and they are made rapidly. 
Flagella-Staining without a Mordant.J — Dr. W. Hessert stains 
flagella, using no mordant, in the following way : — A young agar culture 
is suspended in distilled water, and a film made on a cover-glass. When 
dry, the film is fixed either by passing the cover-glass through the flame 
or by treating it with a saturated alcoholic solution of sublimate. In 
the latter case it must afterwards be washed. When fixed, the prepara- 
tions are treated for 30 to 40 minutes with the staining solution, which 
is frequently heated. The cover-glass is then washed, dried, and mounted 
in Canada balsam. The staining solution recommended is a 10 per cent, 
aqueous dilution of a saturated alcoholic solution of fuchsin. 
* Ann. 1st. d’ Igiene Sper. Univ. Koma, iv. (1894) pp. 167-76. 
t Biol. Centralbl., xiv. (1894) pp. 687-8. 
X Centralbl. f. Bakteriol. u. Parsasitenk., xvi. (1894) pp. 346-7. 
